My guess is that since the tribe owns to the middle of the river, they were given compensation when their land was flooded. In that way, they own half the lake and I would guess half the water. But, do they own half the dam? Since is was stated that they get proceedes from the operation of the dam, then any water removed from the dam would result in less electricity and perhaps less recreational income. That would make sense since all other releases would have to do with normal dam operation, but this would be a specific removal of potential income. The amount seems fairly high, since if this is just lost income I really wonder what they make otherwise. Still, before anyone gets too mad, they probably should look at the original agreements.
Marsha, the problem is this would probably leave less water in the river, which would mean less to spill, a detriment to the salmon. They say it is to help fish habitat, but that would make no sense to pay the tribe for water to do this, since any drawdowns would be essential to normal operations.
The next problem will be when all the tribes downriver decide that it reduces fish runs and decide to sue. Then perhaps other farmers who claim it makes them harder to get water rights down river. If this is to help specific users, it should be them who pay for it. It may be that the state is taking the lead in this and then will require the cities and farmers to pay back their share.